Mold with ejector



, Aug- 30, 1932 y yM. H. MARTlNbELL 1,875,071

MOLD WITH EJEGTOR Filed'l March 14 1929 Patented Aug. 30, 1932 UNITED STATES,

PATENT, cri-ICE MILTON H. MAETINDELL, or TEEN'roN, NEW JERSEY, ASSIGNoE To JOSEPH STONES RUBBER COMPANY, E TEENTON, NEW JEESEMA coEroEATroN or NEW JERSEY MOLD WITH EJEc'roE Application led March 14, 1.929. Serial No. 346,887.

rl`his invention relates to a method and means for molding articles in a permanent mold.

' Heretofore, in the molding of float balls of rubber or the like, the threaded cores employed for the purpose of producing threaded sockets in the oat balls have been formed on pins which were set into bored openings extending into the mold piece from the cavity thereof. When a ball was removed from the mold the core came with it. The core was then unscrewed fromrthe finished ball and replaced in the mold for the next molding operation. In the removal and replacement ofthese core pins the edge ofthe mold around the pin opening was apt to be nicked or damaged, thereby marring the product of the mold thereafter. t

One of the objects of the present invention therefore is the provision of a method and means which avoids such damage to the mold.

Another object is the provision of a method and means which permits the retention of the core pins in the mold at all times.

A further object is the utilizing of the operation of disconnecting the core pin and ball as a means for dislodging the ball from the mold. I

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawing, in which- Fig. 1 is a fragmental sectional view of a multiple cavity mold embodying my invention- Fig. 2 is a similar view showing molded balls in place in the mold cavity;

Fig. 3 is a sectional view of the mold piece in which the core pins are mounted, the latter having been rotated in a direction to disconnect them from the finished balls and dislodge the latter from the mold piece.

In the drawing I have illustrated fragments of two mold pieces and l1 containing a plurality of cavities 12 and 13, respectively, of the desired forms, these cavilties being preferably formed with quarter round grooves at their peripheries in order to produce half round beads on the molded articles at the parting line. The mold pieces 1,0 and 11 are adapted to be brought into proper alignment when the mold is closed by means of the usual dowelpins and to be Secured firmly together by any Suitable clamplng means. y The cavities 13 are formed at their lower ends with the customary necks 14 for the production of reinforcing bosses on the molded balls, in which bosses are located the threaded sockets by means of which connection is made with rods forming part of the mechanism to which-the balls are connected in use. In the mold piece 11, in alignment with the necks 14C, cylindrical openings 15 connect the cavities 13 with the outer side of the mold piece. These openings are counterbored at 16. 17 is a cover plate which is removably secured to the mold piece 11 by screwslS or the like. Before the plate 17 is put in place, however, headed pins 19 are inserted in the openings and counterbores and 16. v These pins have threaded portions 20 extending into the cavities 13 through the centers of the necks 14, constituting the threaded cores. Thek pins 19 are maintained in position 4and prevented from having longitudinal movement by the cover plates 17, which Voverlie the heads ofthe pins. These heads may be Yprovidedwithslots 21 for the reception of a screw-driver, holes 22 ofqsmaller diameter than the heads being bored in the plate 17in alignment with the openings 15, in orderthat the screw-driver maybe insertedf f In carrying out the invention cup-Shaped pieces of rubber are placed in the cavities12 andi13, "the, rubber being pressed down into theneck 14 around the core 20. When all of the cavities are filled, blowing compound is placed within leach of the cups in one mold piece land the two mold pieces are put together and clamped, causing the edges of the cup- Shaped pieces of rubber to engage each other `at lthe parting line of the mold.r The mold is nfow subjectedto vulcanizing heat, the blowing compound giving off gasto expand the rubber against the'walls of the cavities 12 and A13. When vulcanization is completed be removed, and the mold is then ready for af4 new charge, the core pins being maintained continuously inplace. Molded float balls are shown in place in a closed mold at A in Fig. 2, while in Fig. 3v

the balls are shown at A( in the position which they'take after the pins 19.*have been 'rotated to disconnect `the cores from the balls.

i The apparatus and method yconstituting my invention have been herein described by reference 'to float balls, but it isobvious that the invention is of more ork less general appli- Y cation, particularly in connection with non-l 'metallic' articles. Furthermore, for the sake of fully illustrating the. invention, I have described the apparatus and the methodmore or less in detail,but such detailed disclosure is not intended to constitute a limitation upon thescope of the invention. .o

. I-Iaving thus described my invention, what I claim is: A

1. In a permanent mold, a mold piece havy inga molding cavityr therein, a pin rotatably lodge mounted kin said mold piece, said pin having a .threaded portion extending into the said with asocket in the molded article, .and

whereby the unscrewing of thepin will disling afmelding cavity therein, a pin rotatably mounted in said `,mold piece,v said pin having a'threadedportion extending into saidcavthe molded articlefrom said moldy a tool extended through said opening for i' turning said pin, whereby the unscrewing l of the pin will dislodge the molded articlev fromsaid mold piece. i

4:. In a permanent mold, a mold piece having a plurality of moldingcavities therein,

pins rotatably mounted in said v mold piece,

mold piece, a cover plate secured to the eX- l ternal side of said mold piece having openings therein in alignment with ythe said'counterbore but of smaller diameter, and meansin each'of saidheadsadapted to cooperate with` a tool projected through the corresponding opening for turning the-corresponding pin, whereby the unscrewing ofthe pinsfwill dislodge'the-molded articlesfrom said mold piecefjl 5. In a permanent mold for the production ofmolded float balls with threaded sockets, a mold piece having a molding cavity therev in, a. pin rotatably mounted in said mold piece, said pin having a threaded portion eX- eachof said pins having a threaded portion tending into said'eavity tov form a coreyfor'k the formation of `a threaded socket in thev ball, means permitting the rotation of said pinfrom the outer side Lofpsaidmold piece, z

and meansvfor preventing thelongitudinal movement of the pin, whereby-the pin serves -not only as. aV core Vbut also' asa meansjfor dislodgingthe molded' ball from;A saidcavity. 100' Y cavity 'and adapted to threadably engage Y signature. means for preventing longitudinal movement Vof said pin during the rotation thereof, i

MILTON ,MiinriNDEiiiL Intestimony whereof,y I hereunto afix my ity toforni a core for the vproduction of a j:rk .fr o. threaded socket-in the molded article, means ,Y for'preventing .longitudinal movement of said'rpinand means'for rotating thesame,

v 3. 'In a permanent'mold,a mold.Vv vpiece having akmolding cavity therein, a pinr rotatably whereby the unscrewing of the pin will dislodgel the molded article vfrom said mold l Y `ano mountedf'in'said mold piece, said pin having Y n :a threaded portion extendinginto said cavity tov-form a core for the production of a threaded socket in the molded article, and

havingalso a head seated in a counterbore in' the mold piece, al cover plate for the said -mold piece vhaving an opening therein in alignment with' said counterbore o but of i I i o 

